My dad had a fall and suffered a pretty bad brain injury a few years ago. He has since fully recovered aside from more frequent short-term memory loss, but duri

My dad had a fall and suffered a pretty bad brain injury a few years ago. He has since fully recovered aside from more frequent short-term memory loss, but during his multi-week hospital stay, many aspects of his personality, maturity, and abilities changed, almost to the point of extreme dementia. More relevant to this story, one incident I remember clearly was that he started talking about taking care of "him" and changing his diaper. Finally we got around to the fact that he was talking about his first nephew, who was born when my dad was quite young in the 1950s. My dad helped my aunt and grandma take care of him and it was his first exposure to caring for a child. All of those people are 30+ years out of existence now, so it was quite a flashback.